Research on Acidity-Alkalinity Sensor Temperature Compensation Method and Measuring Circuit Design

According to the problems of data errors caused by temperature effect in acidity-alkalinity measurement and low output voltage of sensor electrode, a temperature compensation method and measuring circuit are proposed. In this method, acidity-alkalinity value and temperature are measured by acidity-alkalinity sensor and temperature sensor, measurement data are fused by two-dimensional regression equation to compensate the temperature effect on the acidity-alkalinity measurement accuracy. After measured voltage value passed the amplifier circuit, using error processing method that programmed in the MCU to improve the validity of measured data. The experiment results show that the average measurement error reduced from 18.35% to 5.66%, and this method has certain practical significance.